Shed-forming apparatus for a loom



July 22, 1969 A. SCHNEIDER SHED-FORMING APPARATUS FOR A LOOM 4 Sheets-Sheet 1 Filed Dec. 13, 1966 v25 Eco;

mentor Arfhur Schneider BY WMM JZQV 0463a.

ATTORNEYS .Fuly 22, 1969 A. SCHNEIDER 3,

SHED-FORMING APPARATUS FOR A LOOM Filed Dec. 13. 1966 4 Sheets-Sheet 2 lnvenforz Ari'hur Schneider BY W M LVMQQW ATTORNEYS July 22, 1969 A. SCHNEIDER SHED-FORMING APPARATUS FOR A LQOM 4 Sheets-Sheet 3 Filed De. 13, 1966 Inventor.-

Arfhur Schneider BY M JQZLV Milka.

A TORNEYS July 22, 1969 A. SCHNEIDER 3,456,691

SHED-FORMING APPARATUS FOR A LOOM Filed Dec. 13, 1966 4 Sheets-Sheet 4 Inventor- Arthur Schneider ATTORNEYS United States 3,456,691 SHED-FORMING APPARATUS FOR A LOOM Arthur Schneider, Winterthur, Switzerland, assignor to Sulzer Brothers Limited, Winterthur, Switzerland, :1 Swiss company Filed Dec. 13, 1966, Ser. No. 601,378 (Ilaims priority, application Switzerland, Dec. 15, 1965, 17,347 65 Int. Cl. D03c 13/00, 49/06; D03d 51/20 U.S. Cl. 139-55 8 Claims ABSTRACT OF THE DISCLOSURE The present invention pertains to looms and more particularly to shed-forming apparatus therein.

In looms heretofore proposed the shed is formed by reciprocating harnesses or heddle frames with the heddles supported therein. Jacquard looms are also known in which the warp threads are suspended on Jacquard cords and are controlled thereby. In all of these known looms the tension on the warp threads varies substantially over the weaving cycle of the loom. That is, the tension on the warp threads varies according as they are in upper shed position, in lower shed position or in closed shed position. Moreover, for example in conventional looms having heddle frames, the tension of a warp thread likewise depends on whether that warp thread is controlled in shed position by the front heddle frame or by a heddle frame farther toward the rear, i.e. toward the warp beam end of the loom. The warp tension also depends on whether or not the operation is such as to give a so-called clear" shed, in which all of the warp threads in upper shed position extend in a single plane to the fell of the cloth and similarly for the warp threads in the lower half of the shed. As is well-known, to produce a clear shed it is necessary that the heddle frames behind the first one must have successively higher shed positions, in order that the warp threads controlled thereby may lie in a common plane with those of the heddle frames closer to the cloth end of the loom.

In these known types of looms and also in the Jacquard looms mentioned, relatively large masses must be recip rocated in the shedding process. This requires a powerful drive mechanism which is subjected to heavy wear and which, consequently, has an undesirably short life.

The invention provides a shedding mechanism or motion improved in this respect, and also in respect of control of the tensioning beam or back rest by which warp thread tension is regulated.

In accordance with the invention the shedding motion includes a plurality of levers having two or more arms and hereinafter sometimes called droppers, distributed over the width of the cloth, these levers being provided with openings or eyes for the warp threads and atent C F ice being rocked back and forth in arcurate oscillatory motion for shed formation in timed relation with the picking operation. This makes it possible to effect shed formation with oscillation of relatively small masses only.

Each warp thread passes thorugh a plurality of eyes in one dropper allocated to it. This makes it possible to etfect better separation of the upper and lower halves of the shed, and the shed need not be open so wide as heretofore. Thus for example a shed height of some 15 millimeters suffices for picking of gripper shuttles in gripper shuttletype looms.

Moreover, the invention permits the simple and ready formation of a clear shed as that expression has been hereinabove defined.

In view of the small masses required to be moved in a shed motion according to the invention, the time required for shed changes constitutes a reduced fraction of the loom cycle. Thus with a given picking rate or loom cycle time, there is made available a longer time interval for the picking operation. If instead no exterision of this time is required, it is possible to increase the number of picks per minute.

In one embodiment of the invention the droppers are provided each with three lever arms each having a thread eye formed therein so that two of the arms extend collinearly in opposite directions whereas the third extends perpendicularly to the other two. The transverse arms of a plurality of the droppers are directed substantially oppositely to the corresponding transverse arms of the remainder of the droppers. In such a construction each warp thread is passed through three eyes in its -dropper, namely a separate eye in each of the two longitudinal arms and a third eye in the transverse arm. This makes it possible to maintain a substantially constant tension on the thread for all positions of the dropper, i.e. upper shed and lower shed positions. In closed shed position the tension on the thread is substantially as great as in either of the other two shed positions. The construction may be such that each dropper is shifted backwardly into closed shed position by the tension of its thread after the weft thread has been inserted.

In a preferred embodiment the thread eyes in the longitudinal arms take the shape of slits parallel to the length of those arms. On passage through the slits so formed the warp thread is bent through a small angle only. Danger of injury to the thread by friction is thereby diminished, and thread breakages are likewise reduced.

In one preferred embodiment in accordance with the invention, a tensile member is coupled to each longitudinal arm of each dropper to permit drive of the dropper in timed relation with the picking operation. Advantageously, the tensile members coupled to the front longitudinal arms of all droppers are selectively engageable with the blades or bars of a first group of actuating blades while the tensile members coupled to the rear longitudinal arms of all droppers are selectively engageable with the blades or bars of a second group of actuating blades.

Advantageously, the blades of one blade group are mounted in and between two parallel levers, and the blades of the other groups are mounted in and between two additional levers, all four levers being pivoted on a common stationary shaft. The free ends of the two levers at one end of the blades of both groups are then coupled to a bar which can be reciprocated up and down, toward and away from the said common shaft, and similarly for the two levers at the opposite ends of the blades. The two bars thus provided are reciprocated in timed relation with the picking operation to permit shed formation and change in timed relation therewith. In this form of drive for the shed-forming droppers there is achieved the result that on each shed formation the stress to be applied is the same irrespective of whether the shed to be formed is light or heavy. By a light shed is meant one in which a relatively small number of warp threads are raised to upper shed position. Conversely a heavy shed refers to one in which a large number of warp threads are in upper shed position while a smaller number are in lower shed position. In contrast thereto, it is customary in the looms of the prior art to require substantially greater force for a heavy shed than for a light shed.

In one embodiment of the invention there is provided a bar of permanently magnetized material on each side of the transverse arm of each dropper, these bars extending across all of the droppers. This magnet is effective to attract a transverse arm of any dropper whose warp thread breaks. This attraction may serve as a warp thread breakage and/or loom stopping signal. Preferably, each such magnetic bar is provided with a spring-biased contact rail by means of which the loom is stopped as soon as the transverse arm of a dropper being attracted by a magnetic bar engages with that contact rail. In such a construction, therefore, the droppers also serve to indicate breaks in the warp threads, and automatic stoppage of the loom is thereby effected. The dropper engaging the magnetic bar also identifiers to the loom attendant the warp thread which is broken.

In another embodiment of the invention, a tension beam or back rest is provided with reciprocable motion in the direction of the warp threads in their passage through the shed, this beam being disposed between the warp beam and the droppers. The warp threads pass over this beam and are held in tension thereby, and means are provided for effecting and controlling reciprocating motion of this beam in timed relation with the picking operation. The control for this tension beam can be either mechanical, pneumatic, hydraulic or electric. In this construction a desired maximum tension of the warp threads may be achieved at a desired phase of the loom cycle. Thus for example the tension beam can be moved backwardly toward the warp beam during heating up so that the inserted weft threads will be especially tightly beaten up and bound into the warp. Usually, upon heating up and in view of the increased warp thread tension which results from the rearward motion of the tension beam at that time, the droppers are disengaged from their drive at that moment so that the shed-forming droppers will then move to closed shed position. This achieves a further improved binding in of the weft thread so beaten up. By means of the control device for the tension beam it is however possible to achieve a warp thread tension which is constant throughout the whole loom cycle.

The invention will now be further described in terms of a presently preferred embodiment thereof and with reference with the accompanying drawings in which:

FIG. 1 is a perspective view of the shed-forming apparatus in a loom according to the invention;

FIGS. 2 and 3 are illustrations of details of the apparatus of FIG. 1;

FIGS. 4 to 6 illustrate three positions for particular portions of the apparatus of FIG. 1;

FIG. a shows an alternative form of construction for the droppers of the invention;

FIGS. 7 to 9 illustrate a modified construction in ac cordance with the invention, in three operational posi tions corresponding to those represented in FIGS. 4 to 6 respectively; and

FIGS. 10 and 11 show a further modified construction in two positions of operation.

Referring to FIG. 1, warp threads 21 are delivered from a warp beam not shown over a back rest 22 to the shed-forming thread droppers 1 and 1a which may, for example, be made of sheet steel. The droppers are rotatably mounted on a shaft 5 fixedly supported in the loom. Each of the droppers has the shape of a three-armed lever with two relatively long collinearly extending longitudinal arms 25 and 26 and a transverse arm 27 extending at right angles to the arms 25 and 26. Each of the longitudinal arms includes an eye 24, which may take the shape of a slot whose length is parallel to the length of those longitudinal arms. Each of the cross-arms 27 includes an eye 28. The thread droppers 1 have their transverse arms 27 extending downwardly while the droppers 1a have their arms 27 extending upwardly; in other respects the droppers 1 and 1a may be the same. In any given shed, the droppers 1 form one half of the shed, e.g. the lower half, as illustrated in FIG. 1 while the droppers la form the other half of the shed, e.g. the upper half, upper and lower being here referred to that part of the shed through which the shuttle passes and which is located between the eyes 24 adjacent the cloth end of the loom (the left end in FIG. I) and the fell of the cloth at 35. It is to be understood that one dropper is normally provided for each warp thread, and that the numbers of warp threads and hence of droppers in the two halves of the shed need not be the same.

The shed-forming droppers 1 are shown in FIG. 1 in lower shed position with the longitudinal arms 26 thereof depressed. Arm 26 is the one extending toward the fell of the cloth. The droppers 1a in contrast are in upper shed position with the longitudinal arms 26 thereof elevated. Each of the warp threads 23 of what constitutes, for the shed shown in FIG. 1, the lower half of that shed passes through the eye 24 of the elevated rear arm 25 in one of the droppers 1. From eye 24 this thread then passes downwardly through the eye 28 of the cross arm in its dropper and thence through the eye 24 of the front arm 26 which is in lower shed position. Each of the warp threads 33 of the other half of the shed passes correspondingly through the eye 24 in the depressed rear arm 25 of one of the droppers 1a, thence upwardly through the eye 28 of the crossarm of its dropper and thence through the eye 24 of the front arm 26 of that dropper, which is elevated. The warp threads 23 and 33 together with the longitudinal arms 26 define the shed, indicated at 31. The picking of the weft is effected through this shed, for example by means of a gripper shuttle 32 moving in the direction indicated by the arrow 34 in FIG. 1 and pulling through the shed a weft thread not illustrated in the figure. In FIG. 1 picking mechanism for throw of the shuttle 32 through the shed is indicated in purely diagrammatic fashion at a box 2, driven from a loom drive 3. The loom includes catching mechanism and other conventional elements not shown.

By means of a reed not shown in FIG. 1 but also coupled to the loom drive 3, the picked weft thread is beaten up at the fell 35 to form the fabric 36. The fabric is passed over a breast beam 37 and then onto a cloth beam not shown on which it is rolled up.

A tensile member, for example a steel wire 41 which may alternatively be made of a synthetic material, is fastened as at 50 to each of the arms 25 and 26 on all of droppers 1 and 1a. Each of these members is continued in a downward direction in a tension rod 42 having a hook-shaped end 43. Each of hooks 43 is engageable under a blade 44 so that upon downward motion of the blade 44 the rod 42, cord 41 and corresponding dropper arm 25 or 26 will be drawn downwards. The blades 44 are journaled at their ends in two pairs of levers 13 and 13a, rotatable about ends of a fixed shaft 15. The free ends of the levers 13 and 13a are coupled in pairs as shown in FIG. 1 by means of intermediate elements 45 with bars 17. Each of these bars is coupled to the rod 16 of the piston in a hydraulic drive device 14. The pistons 16 are reciprocated upward and downward in timed relation with the picking operation and thereby impose reciprocating motion on the levers 13 and 13a and hence on the blades 44.

The blades 44 are divided into two groups 47 and 48. The blades of group 47 engage the levers 13a and serve exclusively to draw downwardly the longitudinal arms 26 so as to draw the droppers into lower shed position. The blades of group 48 engage the levers 13 and serve to draw downwardly the arms 25 and thereby to shift the droppers into upper shed position.

Each of the rods 42 passes through the eye 7 of a horizontal tensile member 6 which may for example be a steel wire. One wire 6 is provided for each of the droppers 1 and In, so that there is one wire 6 per warp thread. The wires 6 terminate at the right in FIG. 1 in a stationary step or stair-shaped structure 8 which contains a number of bolts 51, as shown in FIG. 3, to which the wires 6 are fastened. These bolts are subjected to the action of compression springs 9 which tend to draw the wires 6 to the right in FIG. 1. At the left end thereof the the wires 6 lead to a corresponding stationary stairshaped device 8a and terminate each at the armature 52 of an electromagnet 11 (see FIG. 2). Each armature includes a motion-limiting disc which brings up against the device 80 when its electromagnet is deenergized. Each of the wires 6 includes two eyes 7, one for the rod 42 of its dropper belonging to the group 47 and the other for the rod 42 of its dropper belonging to the group 48. Thus the rods 42 connected to the two arms 25 and 26 of each of the droppers 1 and 1a pass through the eyes 7 of a single wire 6.

By means of the stair-shaped devices 8 and 8a, each of rods 42 can be moved successively to the right and left in FIG. 1 according to a pre-estabilshed program. The hook-shaped ends 43 of rods 42 are thus brought into and out of engagement with their associated blades 44. By operation of the program, which can be either electrically or electronically controlled, there is energized for each pick a plurality of electromagnets 11, the plurality changing after each pick. For each magnet so energized, its Wire 6 is pulled to the left in FIG. 1 so that the rod 42 controlled thereby and cooperating with the blade group 47 is brought via its hook 43 into engagement with its blade 44 in group 47 whereas the rod 42 controlled thereby and associated with the group 48 is brought out of engagement with its blade 44 in that group. The remainder of the magnets 11 remaining de-energized, the wires 6 thereof are drawn to the right in FIG. 1 by their springs 9, so that the hooks 43 of the rods 42 of those wires associated with blade group 48 are engaged under the blades 44 of that group while the rods 42 of those wires associated With group 47 are disengaged from under the blades of group 47.

When thereupon the pistons 16 move downwardly, the droppers coupled through wires 6 to the energized magnets will be pulled downwardly, at their lever arms 26, into bottom shed position, while the other droppers will by action of the blade group 48 be drawn downwards at their levers 25, being thereby shifted into upper shed position.

The arrangement is such that at any downward stroke of the pistons 16, and for any one of the droppers 1 and 1a, only one of the two rods 42 coupled to that dropper will be drawn downwardly by one of the blades 44, the other rod 42 of that dropper being out of engagement with its blade 44. In this way it is possible to achieve widely different weaves, including for example Jacquard designs.

The droppers are engaged on the shaft 5 with the transverse arms 27 of some thereof directed upwardly while the others are engaged thereon with their arms 27 directed downwardly. In FIG. 1 those with their arms 27 up are denoted 1a while those with their arms 27 down are denoted 1.

Permanently magnetized bars 55 are provided in front and to the rear (i.e. in the sense of the extension of the warps) of the upwardly extending arms 27, and likewise in front and to the rear of the downwardly extending arms 27. In the event of a warp thread breakage one of these bars will attract into engagement therewith the the arm 27 of the corresponding dropper. Lengthwise of each of the bars 55 there is directed a beam of light from a source 56. This beam is directed to a corresponding or associated photocell 57. Consequently, in the event of warp thread breakage there will occur interruption of one of these light beams by engagement of the transverse arm 27 of the corresponding dropper against one of the bars 55. The loom will then automatically be stopped by operation of the photoelectric device comprising elements 56 and 57. During normal operation the length of the stroke of the blades 44 and the torques opposed thereto (which can be identified as K) which are exerted on each dropper 1 or 1a by the warp thread passing through that dropper are such that even with the dropper in upper or lower shed position, the transverse arms of the droppers cannot be brought into engagement with the magnet bars 55. Consequently, the light beams from the sources 56 reach their corresponding photocells so that the loom is maintained in operation.

In the embodiment of FIGS. 4 to 6 (wherein the cloth end of the loom is at the right), all of the droppers 1. whose transverse arms 27 are in the up position are coupled together by means of a rod shown at 61 in FIG. 4 which extends parallel to the shaft 5. This rod connects with a drive bar 62 which can be horizontally reciprocated from the main drive of the loom. Similarly, all of the droppers 1a whose transverse arms 27 are directed downwardly are coupled together by means of a rod 63 which connects with a horizontally reciprocating drive bar 64.

In the position of the apparatus shown in FIG. 4, the reed 65 is in its retracted position. The warp threads 23 and 33 cross each other at 66 to the right of the shaft 5. By means of the tension of the warp threads, forces K are exerted on the longitudinal arms 25 and 26 by means of which the droppers 1 and 1a are stressed into the intermediate or closed shed position shown in FIG. 5 as soon they are permitted to do so by the bars 62 and 64, Le. as soon as the driving force is removed from these bars. The drive to levers 62 and 64 can however be a positive one in both directions so that the forces K developed by the warp threads are without effect, the droppers being rotated from the position of FIG. 4 to that of FIG. 5 substantially exclusively by operation of the levers 62 and 64.

During the motion of the droppers from the position of FIG. 4 to the closed shed position of FIG. 5, the weft thread inserted by the shuttle 32 is beaten up by the reed 65. The reed is shifted to the beating up position shown in FIG. 5 at the same time as the droppers 1 and 1a move to the closed shed position. Thereupon the reed is retracted and immediately the droppers 1 and 1a shift to the position shown in FIG. 6 with the droppers 1 in the upper shed and the droppers 1a in the lower shed position. The crossing point of the warp threads 23 and 33 is now at 66a to the left of the shaft 5.

In the open shed positions of FIGS. 4 and 6, the path imposed on each warp thread through the three eyes of its dropper is only slightly longer than the path imposed on it when its dropper is in closed shed position as shown in FIG. 5. In consequence thereof, the tension of the warp threads is held substantially constant for all shed positions.

Whereas with drive of the shed-forming droppers 1 and 1a of FIG. 1 by means of the blades 44 and rods 42 of that figure every weaving pattern is possible including those of Jacquard designs, with the drive of the droppers by means of bars 62 and 64 as shown in FIG. 4, the weave can be changed only by changing the distribution of the droppers among the two drive bars 62 and 64 before weaving begins.

In the embodiment of FIGS. 7 to 9, the warp and cloth beams 71 and 72 have been shown. The tension beam or back rest 22 is mounted for adjustable parallel motion in a horizontal direction by means of elongated slots 73 in the loom frame so as to be movable in the direction of the warps. The beam 22 is controlled in this adjustment by means of a hydraulic piston 75 controlled by means of a cam 74 in timed relation with the picking op eration. By means of this piston, hydraulic fluid 76 under pressure, for example oil, is applied against the shaft 77 of beam 22. In the condition of the elements shown in FIG. 8, the beam has been moved to the leftmost position therefor. The warp threads are then subjected to an increased tension. Advantageously this increase in tension occurs at the instant of beating up as is indicated in FIG. 8 by the reed 65, which is at the fell 35 of the cloth.

On the other side of the beam 77, there is connected a hydraulic control device 79, in turn controlled by a valve 78 in a hydraulic supply line connecting thereto. By means of this device 79 and its valve 78, the maximum tension or stress exerted on the warps by the beam 22 can be adjusted. As the reed 65 is restored to the retracted position shown in FIG. 9, rotation of the cam 74 continues so that the control piston 75 and also the beam 22 are returned to the normal position shown in FIG. 9. Simultaneously, the shed change begins; the droppers 1 are shifted from the upper shed position shown in FIG. 7 to the lower shed position of FIG. 9 and the droppers 1a are shifted from lower to upper shed position.

FIGS. 7 to 9 show a further variant form of construction of the warp thread monitoring device comprising the magnetic bars 55. In those figures, each of the bars 55 has associated therewith a contact rail 82 subjected to a spring stress. In the event of breakage of a warp thread, the transverse arm 27 of the corresponding dropper is brought to bear against this rail in consequence of attraction of the dropper by means of the magnetized bar 55. The contact rail 82 being thus shifted, an electric circuit is established by means of which the operation of the loom is stopped.

Modified constructions can be obtained with droppers having, for example, only two eyes for each warp thread and having consequently only two arms and hence the triangular shape shown in FIGS. 10 and 11. With such a construction it is not possible to achieve for all shed positions so nearly a constant warp thread tension as with the embodiments of FIG. 1 to 9. With two-arm droppers however constancy of the thread tension can be achieved by position control of the beam 22 through suitable adjustment of the beam drive elements such as cam 74 and piston 75.

In embodiments using tensile rods 42 and blade assemblies 47 and 48 as shown in FIG. 1, there may be employed pneumatic or electric drive to those blades in place of the hydraulic drives 14 of FIG. 1. In either case the drive to the blade assemblies will be suitably coupled to the main drive of the loom so as to effect shed formation in timed relation to the picking operation, as is illustrated in FIG. 1 by the diagrammatic connecton between the loom drive 3 and the unit 14 visible in that figure. For example, the blades 44 may be driven individually by cams so as to produce a blade drive similar to that applied to conventional heddle frames. Optionally, one may also dispense with the arrangement of wires 6 for selective coupling the rods 42 to the blades 44, the elements 42 and 44 retaining throughout a complete weaving operation, e.g. through the weaving of a length of cloth, a coupling relation initially set up.

The thicker the thread, the longer should be the slit-shaped eyes 24.

The control system 74 to 79 for the beam 22 may be pneumatic or electrical or mechanical in nature and is not restricted to the hydraulic system shown. It can also be applied to the loom shown in FIG. 1. A loom controlled by blades 44 divided into blade groups 47 and 48 can be transformed into a complete Jacquard machine by disconnecting the rods 42 from the blades 44 and connecting the rods 42 directly to the Jacquard control system. This, for example, makes it possible to do a pick on pick" Weave.

The droppers 1 and 1a may be provided between their longitudinal arms 25 and 26 with more than a single crossarm. Thus, for example, they may possess the crossarm denoted 27 in FIG. 5 and additionally, two diagonal crossarms 60 as shown in FIG. 5a between the crossarm 27 and the longitudinal arms 25 and 26. By means of the arms 27 and 60 it is then possible to couple together the droppers in each of several groups of droppers which are to have a common motion, such coupling being effected as to each such group by means of a bar such as the bars 61 and 63 of FIG. 4. Each of these groups may then be reciprocatingly driven by means of a lever of the type shown at 62 and 64 in FIG. 4. As a consequence of the relatively large motions of the thread eyes 24 due to the large length of the longitudinal arms 25 and 26 by comparison with the crossarms 60 and 27, it is sufficient to employ a relatively small throw on the arms 60 and 27 and yet to obtain a shed of height sufficient for insertion of the shuttle.

The invention can be employed in automatic looms employing either shuttles carrying a supply of weft on a pirn, or in gripper shuttle looms in which the weft storage is outside the shed. It can also be employed in ribbon looms.

While the invention has been described hereinabove in terms of a number of presently preferred embodiments thereof, the invention itself is not limited to these embodiments but rather comprehends all modifications on and departures therefrom properly falling within the spirit and scope of the appended claims.

I claim:

1. Shed-forming apparatus for a loom comprising two groups of pivotally mounted levers disposed crosswise of the loom, pivotal mounting means for said levers, each of said levers having at least three eyes formed therein for the passage of a warp thread therethrough, each of said levers being pivoted on said mounting means at a point thereof between and substantially on a line joining two of said eyes, and means to impose oscillatory arcuate motion on said levers.

2. Shed-forming apparatus according to claim 1 wherein each of said levers includes two substantially collinear arms and a third arm extending transversely of said collinear arms, each of said arms having one of said thread eyes formed therein.

3. Shed-forming apparatus according to claim 2 wherein the eyes in said collinear arms are elongated in directions substantially parallel to the length of those arms.

4. Shedforming apparatus according 'to claim 1 wherein said means to impose motion include, for each of said levers, two tensile members coupled thereto on opposite sides of the pivotal mounting thereof.

5. Shed-forming apparatus according to claim 4 wherein said means to impose motion further comprise two pluralities of blades, and means for selectively coupling one of said tensile members from each of said levers to a blade in a first one of said pluralities while decoupling the other of said tensile members from a blade in the other of said pluralities.

6. Shed-forming apparatus according to claim 2 comprising a magnetized bar disposed on either side of and adjacent to the transverse arms of said levers.

'7. Shed-forming apparatus according to claim 6 including a resiliently supported contact member adjacent each of said bars and between such bars and said transverse arms.

References Cited UNITED STATES PATENTS Stoehr 139-59 Battner 139-55 Sakano 13955 X Wiseman l39-337 10 3,011,526 12/1961 Nelson 13955 X 3,105,524 10/1963 Enloe 139-110 FOREIGN PATENTS 34,035 12/ 1964 Germany.

842,688 3/ 1939 France.

884,629 7/ 1953 Germany.

502,006 3/ 1939 Great Britain.

US. Cl. X.R. 

